Electric distribution systems often include a plurality of power sources and/or power distribution points, such as generating plants and/or electric substations, as well as a plurality of electric loads. Each of these power sources nominally may be configured to provide an electric current to a portion of the plurality of electric loads that are present in a specific region, zone, or other area of the electric distribution system. The electric current may be provided through one or more electric conduits, such as distribution lines or power lines, from the power source to the portion of the plurality of electric loads. Within a given area, power distribution may include a radial topology in which each electric load is supplied by a single power source. Within the radial topology, the electric distribution lines may be configured such that certain electric loads may be upstream, or closer to a power source associated with the given area than other, downstream, loads.
When an electric fault, or fault, occurs within an impacted area of the electric distribution system, one or more isolation devices may be utilized to electrically isolate the fault from the remainder of the impacted area. As used herein, the phrase “impacted area” may refer to any suitable region, zone, and/or area of the electric distribution system that includes one or more faults and which also includes and/or is in electrical communication with one or more electric loads and one or more power sources. A power source that is present within an impacted area also may be referred to herein as an impacted power source.
As used herein, “electrical communication” may include and/or refer to the use and/or presence of any suitable structure to provide an electrical conduit for delivery of electric current between two or more devices. As a non-exclusive illustrative example, placing a first device in electrical communication with a second device may include delivery of electric current, which also may be referred to herein as transfer of electric current, between the first device and the second device if a voltage, or potential, of the first device is different than a voltage, or potential, of the second device. As another non-exclusive illustrative example, placing the first device in electrical communication with the second device may include providing an electrical conduit and electrically connecting or coupling the first device with the second device. However, if no voltage difference, or potential difference, exists between the two devices, no electric current may flow therebetween despite the devices being electrically connected, electrically coupled, or otherwise configured for electrical communication therebetween.
Isolation of a region of the impacted area produces an outage area that may not receive electric current from the impacted power source. This isolation may include utilizing an isolation device that is upstream from the fault to isolate the fault from an upstream portion of the impacted area, which includes the impacted power source, as well as utilizing an isolation device that is downstream from the fault to isolate the fault from the remaining, downstream, portion of the impacted area.
After the fault has been isolated, power may be provided from the impacted power source to the upstream portion of the impacted area while the fault is being repaired. This time to repair the fault may be referred to as the fault reparation time. However, the electric distribution system may not be configured to bypass the fault and also provide electric current from the impacted power source to the downstream portion of the impacted area. Thus, the downstream portion of the impacted area may not receive electric current from the impacted power source during the fault reparation time.
In order to provide electric current to the downstream portion of the impacted area, which may include a sub-portion of the outage area, the electric distribution system may include a network and/or web of areas and/or electric conduits that may be selectively configured to provide electric current to the selected portion during the fault reparation time. This provision of electric current to the selected portion of the impacted area may include providing the electric current to the selected portion from an alternative power source other than the impacted power source. The alternative power source also may be referred to as a restoration power source and nominally may be associated with a different, or restoration, area of the electric distribution system. The sub-portion of the outage area also may be referred to herein as a selected portion of the impacted area, a selected portion of the electric distribution system, a selected portion of the outage area, and/or a selected portion.
The restoration power source may include a maximum, or rated, electric power output. In addition, the electric conduits may provide for the delivery of electric current between the restoration power source and/or the restoration area. Furthermore, the selected portion, or the electrical conduits thereof, may include a maximum, or rated, current carrying capacity. A portion of this rated power output and/or rated current carrying capacity may be utilized by a plurality of electric loads that are associated with, or nominally associated with, the restoration area. Thus, under certain conditions, the restoration area may not include enough excess capacity to provide the electric current to the selected portion without increasing the excess capacity of the restoration area and/or decreasing the electric load that is applied by the selected portion.